Topic: Heavy-to-Light Semileptonic Decays through N^3LO in QCD

Speaker: Dr. Xin Guan

Coordinates: PCFT C1124, 16:00, Thursday, September 3

Abstract: Precision determinations of V_ub are central to CKM-unitarity tests, with future B-factory measurements targeting percent-level precision. Exploiting this potential requires perturbative predictions with matching accuracy, especially for observables subject to kinematic cuts. We present the first complete QCD calculation of all five heavy-to-light hadronic structure functions through (N^3LO), using a hybrid strategy that combines linear interpolation with series solutions of differential equations. Applications include the inclusive decay width, the (q^2) spectrum, and charged-lepton energy moments. These results provide the perturbative foundation for future precision studies of semileptonic heavy-quark decays. 

Speaker Profile: Xin Guan is currently a postdoctoral researcher at SLAC National Accelerator Laboratory. He received his bachelor’s degree from Zhejiang University in 2018 and his PhD from Peking University in 2023. His research focuses on methods for higher-order perturbative calculations and their applications in collider physics.